covid-calculator.js

function calculateIntervals(mortality = 0.001 /* a number from 0-1 for proportion that will die */) {
             const doubling = 2.11578003167; // based on New York's doubling rate in deaths between 1st death and April 1st
             const seedDailyDeaths = 505; // number of Deaths on April 1st
             const incubation = 14; // average days from start to death
             
             let getDay0 = (deaths) => {
               let doublingTime = (Math.log(deaths / mortality) * doubling) / Math.log(2);

               return  doublingTime + incubation;
             }
             let casesForDay = (day) => {
               return Math.pow(2, day / doubling);
             }
             let deathsForDay = (day) => {
                return mortality * Math.max(0, casesForDay(day - 14));
             }
             let resolvedForDay = (day) => {
                 return (1 - mortality) * Math.max(0, casesForDay(day - 14));
             }
             let fix = n => parseInt(n.toFixed(0), 10).toLocaleString();
             let totalCases = 1;
             let activeCases = 1;
             let totalDeaths = 0;
             let totalResolved = 0;
             let daysSinceCase0 = getDay0(seedDailyDeaths);

             for (let i = 0; i < daysSinceCase0; i++) {
               let dailyCases = casesForDay(i);
               let dailyDeaths = deathsForDay(i);
               let dailyResolved = resolvedForDay(i);
               totalDeaths += dailyDeaths;
               totalCases += dailyCases;
               totalResolved += dailyResolved;

               console.log({
                 day: i,
                 dailyCases: fix(dailyCases),
                 dailyDeaths: fix(dailyDeaths),
                 dailyResolved: fix(dailyResolved),
                 totalCases: fix(totalCases),
                 totalDeaths: fix(totalDeaths),
                 totalResolved: fix(totalResolved)
               });
             }
         }